Charge density contour map

FIGURE 1. Laplacian of the charge density contour map of CH3CI in the HCC1 plane. Reprinted with permission from Z. Shi and R. J. Boyd,./. Phys. Chem., 95, 4698. Copyright (1991) American Chemical Society... 

Valence charge density contour maps from pseudopotential (LDA) calculations are presented in [4, 5, 12] see also [7]. 

A map of the electron density distribution around these atoms provides important information. It tells us to what distance from the adatom the surface is perturbed or, in catalytic terms, how many adsorption sites are promoted or poisoned by the adatom. The charge density contours in Fig. 6.27 are lines of constant electron density. 

In a later paper, the authors218 analysed the charge re-distribution in more detail, using electron density contour maps. An energy-level correlation diagram shows no correlations between bonding levels and antibonding levels in the product. 

Such an expression has previously been used for comparative purposes, for the study of interaction between two molecular species, by computing the electrostatic potential of the first partner and by assuming some point charge model as representative of the charge distribution of the second partner. We also plan to extend this concept in a more subtle way by using an electron density contour map to describe the charge distribution of the second partner as a function of the space surrounding this second partner. 

Fig. 7. Maps of the electronic charge density in the (110) planes In the ordered twin with (111) APB type displacement. The hatched areas correspond to the charge density higher than 0.03 electrons per cubic Bohr. The charge density differences between two successive contours of the constant charge density are 0.005 electrons per cubic Bohr. Atoms in the two successive (1 10) planes are denoted as Til, All, and T12, A12, respectively, (a) Structure calculated using the Finnis-Sinclair type potential, (b) Structure calculated using the full-potential LMTO method.

Figure 6.17 Contour map of p in the interatomic surface associated with the CC bond critical point in ethene. The plane of the plot is perpendicular to the molecular plane. The C and two H nuclei are projected onto the plane of the plot to indicate the orientation of the molecule. We see that electronic charge is preferentially accumulated in the direction perpendicular to the molecular plane, giving an elliptical shape to the electron density in this plane.

Figure 6.18 Contour maps of the ground state electronic charge distributions for the period 2 diatomic hydrides (including H2) showing the positions of the interatomic surfaces. The outer density contour in these plots is 0.001 au. (Reproduced with permission front Bader [1990].)...

Figure 1.17. Electron charge density difference contour map for CO on Ni(100) and CO on Ni(100)/H in atop sites, derived from DFT calculations.

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